[vsnet-grb-info 2085] GRB 050904: photometric redshift

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  3924
SUBJECT: GRB 050904: photometric redshift
DATE:    05/09/05 18:55:57 GMT
FROM:    Daniele Malesani at SISSA-ISAS,Trieste,Italy  <malesani at sissa.it>

L.A. Antonelli, A. Grazian (INAF/OAR), P. D'Avanzo (INAF/OABr), V. Testa 
(INAF/OAR), S. Covino, G. Tagliaferri, G. Chincarini (INAF/OABr), A. 
Fernandez-Soto (Univ. Valencia), D. Malesani (SISSA), F. Fiore and L. 
Stella (INAF/OAR) report on behalf of the MISTICI collaboration:

"We observed the field of GRB 050904 (Cummings et al., GCN 3910; Mineo 
et al., GCN 3920) with the ESO VLT-UT1, in the J, H, and K bands (with 
ISAAC) and in the I band (with FORS2).

The afterglow (Haislip et al., GCN 3913; D'Avanzo et al., GCN 3921) is 
detected in all filters, including the I band.

We derive for this source a photometric redshift z = 6.10 (+0.37, 
-0.12;  90% confidence) by adopting a chi square minimization technique 
(Fontana et al., 2000, AJ, 120, 2206). This is in agreement with the 
result of Haislip et al. (GCN 3919).

This message can be cited."